1. Field of the Invention
The present invention relates to a boiling water reactor core shroud head bolt removal tool, and, more particularly, the present invention relates to a tool for ensuring safe removal and installation of core shroud head bolts to the proper position.
2. Description of the Related Art
Core shrouds are components of boiling water nuclear reactors; they are cylindrical structures that surround the core to provide a barrier to separate the downward coolant flow through the annulus from the upward flow through the core. The core shrouds also structurally support and align the fuel assemblies, steam separator assemblies, and control rod guide tubes. A head sits atop the shroud and creates an upper plenum into which a two-phase steam/water mixture enters from the core and is directed to steam separation equipment.
The core shroud head must be removed to access the core for refueling and inspection of the core internals. During removal and installation of the core shroud head, it is necessary to de-tension and tension the core shroud head bolts. These bolts have a spring pushing upward against a retainer, which locks the nut on the shroud head bolt assembly, preventing the nut from rotating. Due to many years of service, and with the accumulation of grit and grime, the retainers may not return to the locked position with just spring pressure. What is needed is a tool that ensures removal and replacement of the core shroud head bolts with the spring retainers in the proper position.